Orthopedics Today Grand Rounds

A 19-year-old woman with hip pain 5 years after previous femoral head microfracture

A 19-year-old woman presented with a 5-year history of left hip pain and dysfunction. She first noticed pain and popping sensations in her left hip at age 13 years when she was involved in competitive track and field. After failing conservative management, she underwent left hip arthroscopy with an iliopsoas release and femoral head microfracture at an outside institution. The patient had several months of relief following the procedure, however her symptoms returned and worsened in subsequent years. Currently, she reports groin pain with nearly all activity and experiences mechanical popping sensations with deep flexion. She continues to perform home stretching and strengthening exercises, which provide no resolution of her pain. She is unable to run and has trouble with walking for prolonged periods. There is no past medical history of significance except a history of nickel allergy. The patient does not use nicotine. Her medications include over-the-counter NSAIDs that provide minimal relief.

On examination, the patient demonstrates a non-antalgic gait. Her left hip has no skin changes or noticeable swelling in the groin or trochanteric area. Range of motion of the left hip reveals symmetric flexion and extension, but there is pain with passive flexion beyond 90°. There is a noticeable difference in hip motion in the prone position with 20° more internal rotation of the left hip compared to the right hip. Flexion, adduction and internal rotation stress of the left hip results in significant groin pain. Flexion, abduction and external rotation elicits pain, but to a lesser extent. The right lower extremity exam is benign. Her neurovascular exam from the hip to ankles is normal and symmetric.

Anterior-posterior (AP) pelvic and modified 45° Dunn views of the left hip were viewed. The lateral alpha angle on the left measured 46.3° compared to 34.4° on the right. The anterior and lateral center-edge angle of the left hip measures 29° and 37°, respectively. CT assessment demonstrates increased femoral anteversion of 32° on the left and 23° on the right. A 3T-weighted MRI for intra-articular assessment demonstrates a labral tear and femoral head cartilage lesion (Figure 1).

The patient underwent a diagnostic arthroscopy to assess the intra-articular pathology, specifically the integrity of the femoral head and acetabular cartilage. The examination demonstrated a complex acetabular labral tear with intra-substance degeneration between the 11 o’clock and 3 o’clock position (Figure 2). The femoral head showed evidence of previous microfracture with extensive chondromalacia in the anterior portion of the weight-bearing zone, including two areas of Outerbridge grade 4 chondromalacia greater than 2 cm in diameter. The acetabular cartilage was intact.

Figure 1. The AP pelvic radiograph (a), modified 45° Dunn view (b) and a select sagittal T-2 cut (c) show evidence of a cartilage defect in the weight-bearing zone.
Figure 2. Arthroscopic views show the femoral head cartilage defect (a) and the labral tear (b).

Source: Brett D. Crist, MD, FAAOS, FACS, FAOA

How would you manage this patient?
See answer on the next page.

FAI with labral degeneration, femoral head cartilage defect status after failed marrow stimulation, congenital increased anteversion

Given these findings, a complete surgical plan to address all her pathology was presented to the patient and her family. It consisted of a surgical hip dislocation with allograft labral reconstruction, femoral head osteochondral allograft transplantation and a derotational proximal femoral osteotomy to address the increased proximal femoral anteversion.

Surgical procedure

A modified Gibson approach was performed in the lateral position. Under fluoroscopic guidance, the blade plate chisel path through the femoral neck was created for the eventual insertion of a 95° blade plate to stabilize the proximal femoral rotational osteotomy. Surgical dislocation of the left hip was performed using a greater trochanteric (GT) osteotomy as described by Reinhold Ganz, MD, and colleagues. A step-cut GT osteotomy was not used due to the need for blade plate fixation.

A 3.5-cm section of labrum that incorporated the complex acetabular labral tear from the anterior insertion to the 11 o’clock position was resected. A prepared tibialis anterior tendon allograft was anchored to the acetabular rim using suture anchors at 1-cm intervals and it was repaired to the remaining intact labrum posteriorly. The residual cam lesion was then isolated and the femoral head and neck osteoplasty was performed. The femoral head was assessed and a 4-cm diameter area of grade 4 chondromalacia was evident in the weight-bearing zone. It was determined that two osteochondral allograft plugs that measured 25 mm and 15 mm would provide sufficient coverage for the area (Figure 3). The grafts were cut from a size-matched fresh allograft and included no more than 8 mm of total thickness including subchondral bone. The bone sides of the grafts were soaked in bone marrow aspirate concentrate taken from the ipsilateral iliac crest and were press fit into the prepared femoral head defects (Figure 4).

The hip was reduced and the capsule was closed. The GT osteotomy was reduced and provisionally stabilized with Kirschner wires. A 95° blade plate was then impacted into the previously prepared chisel pathway. A reference K-wire was inserted perpendicular to the anatomic axis of the femoral shaft above the osteotomy and a 2-mm reference drill bit was inserted parallel to the first wire distal to the planned osteotomy site and the distal end of the plate to create a rotational reference. The proximal femoral osteotomy was completed in the subtrochanteric region and the caudal segment was rotated 20° externally to decrease the femoral anteversion to approximately 15° using a sterile goniometer to determine the resultant difference of the initially parallel references. The osteotomy was reduced and the blade plate was secured to the shaft in compression using an articulating tensioning device, fixing both the femoral and GT osteotomies. A lateral fluoroscopy view of the knee and axial view of the femoral neck were used to verify that the residual femoral anteversion was approximately 15°.

Figure 3. An intraoperative image of the dislocated left femoral head shows evidence of the large cartilage lesion on the superior surface (a) and instrumentation used to remove circular plugs of osteochondral tissue in preparation for graft placement (b).
Figure 4. Shown are preparation of the osteochondral allograft plugs (a) and the femoral head after insertion of the osteochondral allograft plugs was done (b).
Figure 5. A postoperative AP radiograph (a) is shown, as well as an AP radiograph at 1-year postoperatively following proximal femoral hardware removal (b).

The patient remained flat-foot weight-bearing on the operated extremity for 6 weeks with no active abduction. She was prescribed daily vitamin D and calcium and 50,000 IU of ergocalciferol weekly for 8 weeks, as well as 500-mg naproxen twice a day for 4 weeks to prevent heterotopic ossification.

The postoperative radiograph and a radiograph at 1-year follow-up with interval femoral hardware removal showed no evidence of graft collapse (Figure 5). The patient returned to near full activity and was able to perform 8-mile hikes without pain or discomfort. She was cleared to start running and jumping.

Discussion

Femoral cartilage lesions of the hip are significant pain generators and, in addition to acetabular labral tears, can result in a sensation of painful catching or locking. In patients undergoing hip arthroscopy, the presence of chondral injuries is associated with decreased patient-reported outcome scores when compared with patients without these lesions.

Treatment options for cartilage lesions of the hip mimic those in other large joints and include debridement, marrow stimulation, autologous chondrocyte implantation (ACI) and osteochondral autograft and allograft transplant. Once all nonoperative treatments have been exhausted, a thorough understanding of the full hip pathology and underlying etiology for the cartilage lesion needs to be determined. In patients with femoroacetabular impingement, any pincer or cam deformity must be addressed and, in cases of dysplasia, indicated osteotomies can be performed concomitantly with the cartilage repair. Hip instability should also be treated with capsule and labral repair or reconstruction.

In the presented case, a surgical dislocation was chosen over arthroscopic management of the patient because it facilitated treatment of the multifactorial hip pathology, including version correction, labral reconstruction, osteochondroplasty of the residual cam lesion and large osteochondral autograft transfer system (OATS). Given the size of the patient’s cartilage lesion, ACI or OATS would be preferred to marrow stimulation. Marrow stimulation in the hip is generally indicated for cartilage lesions of less than 2 cm in diameter. Darrin J. Trask, MD, and James S. Keene, MD, reported that 60% of their 70-patient cohort had good to excellent results at 2 years. Marrow stimulation was not chosen because our patient failed a previous marrow stimulation procedure and her cartilage defect at the time of arthroscopy was at least 2 cm. We elected to perform allograft reconstruction over ACI given that, in the knee literature, results of ACI following failed marrow stimulation is inferior to OATS. This may be due to changes in the subchondral bone that occur following marrow stimulation, which make it less receptive to cell-based therapies.

Marvin H. Meyers, MD, first reported the results of OATS for large femoral head lesions. He observed 80% positive results in 15 patients who did not need continued systemic corticosteroids and had a follow-up time between 9 and 63 months. Lason O. Oladeji, MS, and colleagues reviewed the mid-term outcomes of 10 patients with an average follow-up of 1.4 years. Seventy percent had successful functional outcomes, while 30% were unsuccessful and subsequently converted to total hip arthroplasty. All of the failures included acetabular involvement or whole femoral head avascular necrosis. In the largest series to date, Xin Y. Mei, MD, and colleagues reviewed 22 patients younger than 50 years who underwent femoral head OATS with an average size of 5.53 cm2. At a mean follow-up of 68.8 months, the modified Harris Hip Score improved on average from 48.9 to 77.4. Graft survivorship was 86.4 ± 7.3% at 2 years, 78.5 ± 10.0% at 5 years and 67.3 ± 13.5% at 9 years.

In conclusion, the optimal management of femoral cartilage lesions of the hip in the young patient remains challenging with allograft transplant being a viable option in the correctly indicated patient.

Disclosures: Crist and Drager report no relevant financial disclosures.

A 19-year-old woman presented with a 5-year history of left hip pain and dysfunction. She first noticed pain and popping sensations in her left hip at age 13 years when she was involved in competitive track and field. After failing conservative management, she underwent left hip arthroscopy with an iliopsoas release and femoral head microfracture at an outside institution. The patient had several months of relief following the procedure, however her symptoms returned and worsened in subsequent years. Currently, she reports groin pain with nearly all activity and experiences mechanical popping sensations with deep flexion. She continues to perform home stretching and strengthening exercises, which provide no resolution of her pain. She is unable to run and has trouble with walking for prolonged periods. There is no past medical history of significance except a history of nickel allergy. The patient does not use nicotine. Her medications include over-the-counter NSAIDs that provide minimal relief.

On examination, the patient demonstrates a non-antalgic gait. Her left hip has no skin changes or noticeable swelling in the groin or trochanteric area. Range of motion of the left hip reveals symmetric flexion and extension, but there is pain with passive flexion beyond 90°. There is a noticeable difference in hip motion in the prone position with 20° more internal rotation of the left hip compared to the right hip. Flexion, adduction and internal rotation stress of the left hip results in significant groin pain. Flexion, abduction and external rotation elicits pain, but to a lesser extent. The right lower extremity exam is benign. Her neurovascular exam from the hip to ankles is normal and symmetric.

Anterior-posterior (AP) pelvic and modified 45° Dunn views of the left hip were viewed. The lateral alpha angle on the left measured 46.3° compared to 34.4° on the right. The anterior and lateral center-edge angle of the left hip measures 29° and 37°, respectively. CT assessment demonstrates increased femoral anteversion of 32° on the left and 23° on the right. A 3T-weighted MRI for intra-articular assessment demonstrates a labral tear and femoral head cartilage lesion (Figure 1).

The patient underwent a diagnostic arthroscopy to assess the intra-articular pathology, specifically the integrity of the femoral head and acetabular cartilage. The examination demonstrated a complex acetabular labral tear with intra-substance degeneration between the 11 o’clock and 3 o’clock position (Figure 2). The femoral head showed evidence of previous microfracture with extensive chondromalacia in the anterior portion of the weight-bearing zone, including two areas of Outerbridge grade 4 chondromalacia greater than 2 cm in diameter. The acetabular cartilage was intact.

Figure 1. The AP pelvic radiograph (a), modified 45° Dunn view (b) and a select sagittal T-2 cut (c) show evidence of a cartilage defect in the weight-bearing zone.
Figure 2. Arthroscopic views show the femoral head cartilage defect (a) and the labral tear (b).

Source: Brett D. Crist, MD, FAAOS, FACS, FAOA

How would you manage this patient?
See answer on the next page.

PAGE BREAK

FAI with labral degeneration, femoral head cartilage defect status after failed marrow stimulation, congenital increased anteversion

Given these findings, a complete surgical plan to address all her pathology was presented to the patient and her family. It consisted of a surgical hip dislocation with allograft labral reconstruction, femoral head osteochondral allograft transplantation and a derotational proximal femoral osteotomy to address the increased proximal femoral anteversion.

Surgical procedure

A modified Gibson approach was performed in the lateral position. Under fluoroscopic guidance, the blade plate chisel path through the femoral neck was created for the eventual insertion of a 95° blade plate to stabilize the proximal femoral rotational osteotomy. Surgical dislocation of the left hip was performed using a greater trochanteric (GT) osteotomy as described by Reinhold Ganz, MD, and colleagues. A step-cut GT osteotomy was not used due to the need for blade plate fixation.

A 3.5-cm section of labrum that incorporated the complex acetabular labral tear from the anterior insertion to the 11 o’clock position was resected. A prepared tibialis anterior tendon allograft was anchored to the acetabular rim using suture anchors at 1-cm intervals and it was repaired to the remaining intact labrum posteriorly. The residual cam lesion was then isolated and the femoral head and neck osteoplasty was performed. The femoral head was assessed and a 4-cm diameter area of grade 4 chondromalacia was evident in the weight-bearing zone. It was determined that two osteochondral allograft plugs that measured 25 mm and 15 mm would provide sufficient coverage for the area (Figure 3). The grafts were cut from a size-matched fresh allograft and included no more than 8 mm of total thickness including subchondral bone. The bone sides of the grafts were soaked in bone marrow aspirate concentrate taken from the ipsilateral iliac crest and were press fit into the prepared femoral head defects (Figure 4).

The hip was reduced and the capsule was closed. The GT osteotomy was reduced and provisionally stabilized with Kirschner wires. A 95° blade plate was then impacted into the previously prepared chisel pathway. A reference K-wire was inserted perpendicular to the anatomic axis of the femoral shaft above the osteotomy and a 2-mm reference drill bit was inserted parallel to the first wire distal to the planned osteotomy site and the distal end of the plate to create a rotational reference. The proximal femoral osteotomy was completed in the subtrochanteric region and the caudal segment was rotated 20° externally to decrease the femoral anteversion to approximately 15° using a sterile goniometer to determine the resultant difference of the initially parallel references. The osteotomy was reduced and the blade plate was secured to the shaft in compression using an articulating tensioning device, fixing both the femoral and GT osteotomies. A lateral fluoroscopy view of the knee and axial view of the femoral neck were used to verify that the residual femoral anteversion was approximately 15°.

PAGE BREAK
Figure 3. An intraoperative image of the dislocated left femoral head shows evidence of the large cartilage lesion on the superior surface (a) and instrumentation used to remove circular plugs of osteochondral tissue in preparation for graft placement (b).
Figure 4. Shown are preparation of the osteochondral allograft plugs (a) and the femoral head after insertion of the osteochondral allograft plugs was done (b).
Figure 5. A postoperative AP radiograph (a) is shown, as well as an AP radiograph at 1-year postoperatively following proximal femoral hardware removal (b).

The patient remained flat-foot weight-bearing on the operated extremity for 6 weeks with no active abduction. She was prescribed daily vitamin D and calcium and 50,000 IU of ergocalciferol weekly for 8 weeks, as well as 500-mg naproxen twice a day for 4 weeks to prevent heterotopic ossification.

The postoperative radiograph and a radiograph at 1-year follow-up with interval femoral hardware removal showed no evidence of graft collapse (Figure 5). The patient returned to near full activity and was able to perform 8-mile hikes without pain or discomfort. She was cleared to start running and jumping.

Discussion

Femoral cartilage lesions of the hip are significant pain generators and, in addition to acetabular labral tears, can result in a sensation of painful catching or locking. In patients undergoing hip arthroscopy, the presence of chondral injuries is associated with decreased patient-reported outcome scores when compared with patients without these lesions.

Treatment options for cartilage lesions of the hip mimic those in other large joints and include debridement, marrow stimulation, autologous chondrocyte implantation (ACI) and osteochondral autograft and allograft transplant. Once all nonoperative treatments have been exhausted, a thorough understanding of the full hip pathology and underlying etiology for the cartilage lesion needs to be determined. In patients with femoroacetabular impingement, any pincer or cam deformity must be addressed and, in cases of dysplasia, indicated osteotomies can be performed concomitantly with the cartilage repair. Hip instability should also be treated with capsule and labral repair or reconstruction.

In the presented case, a surgical dislocation was chosen over arthroscopic management of the patient because it facilitated treatment of the multifactorial hip pathology, including version correction, labral reconstruction, osteochondroplasty of the residual cam lesion and large osteochondral autograft transfer system (OATS). Given the size of the patient’s cartilage lesion, ACI or OATS would be preferred to marrow stimulation. Marrow stimulation in the hip is generally indicated for cartilage lesions of less than 2 cm in diameter. Darrin J. Trask, MD, and James S. Keene, MD, reported that 60% of their 70-patient cohort had good to excellent results at 2 years. Marrow stimulation was not chosen because our patient failed a previous marrow stimulation procedure and her cartilage defect at the time of arthroscopy was at least 2 cm. We elected to perform allograft reconstruction over ACI given that, in the knee literature, results of ACI following failed marrow stimulation is inferior to OATS. This may be due to changes in the subchondral bone that occur following marrow stimulation, which make it less receptive to cell-based therapies.

PAGE BREAK

Marvin H. Meyers, MD, first reported the results of OATS for large femoral head lesions. He observed 80% positive results in 15 patients who did not need continued systemic corticosteroids and had a follow-up time between 9 and 63 months. Lason O. Oladeji, MS, and colleagues reviewed the mid-term outcomes of 10 patients with an average follow-up of 1.4 years. Seventy percent had successful functional outcomes, while 30% were unsuccessful and subsequently converted to total hip arthroplasty. All of the failures included acetabular involvement or whole femoral head avascular necrosis. In the largest series to date, Xin Y. Mei, MD, and colleagues reviewed 22 patients younger than 50 years who underwent femoral head OATS with an average size of 5.53 cm2. At a mean follow-up of 68.8 months, the modified Harris Hip Score improved on average from 48.9 to 77.4. Graft survivorship was 86.4 ± 7.3% at 2 years, 78.5 ± 10.0% at 5 years and 67.3 ± 13.5% at 9 years.

In conclusion, the optimal management of femoral cartilage lesions of the hip in the young patient remains challenging with allograft transplant being a viable option in the correctly indicated patient.

Disclosures: Crist and Drager report no relevant financial disclosures.